INTECIN   20395
INSTITUTO DE TECNOLOGIAS Y CIENCIAS DE LA INGENIERIA "HILARIO FERNANDEZ LONG"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Critical Behavior of the Magnetization and Thermal Behavior in the Fe70Nb10B20 Metallic Glass
Autor/es:
A. ROSALES-RIVERA; A.A. VELÁSQUEZ-SALAZAR; D.F. GÓMEZ-MONTOYA; H.A. GIRALDO-DAZA; F. D. SACCONE
Lugar:
Cancún
Reunión:
Simposio; International Symposium on Metastable, Amorphous and Nanostructured Materials (ISMANAM 2014); 2014
Institución organizadora:
CONACyT
Resumen:
A study of the critical behavior of the magnetization and thermal behavior in Fe70Nb10B20 metallic glass is presented. This sample was prepared in form of ribbon by a melt spinning technique and its structural state was checked using X-ray diffraction with CuK radiation. The temperature dependence of the magnetization was measured using temperature cycling (H fixed) with a Vibrating Sample Magnetometer (VSM-VersaLab by Quantum Design) at fixed external magnetic fields. H was applied along the longitudinal direction of the ribbon. The temperature and field were varied in the ranges 300 ≤ T ≤ 950 K and 0 < H ≤ 10 kOe, respectively. In the temperature cycling measurements, the sample first is subject to external magnetic field at room temperature and then is heated to high temperature. Then the sample is cooled from the high temperature state to room temperature. Data were obtained for consecutive T steps, stabilizing T with a precision of  0.02 K before each reading. In the heating procedure, the magnetization curves exhibit a Hopkinson-type weak anomaly at a certain temperature THo just below the amorphous Curie temperature TCurie,am with increasing temperature and falls basically to zero before that the sample reaches its crystallization temperature. In contrast, when the sample is cooled, the magnetization curves exhibit a sharp peak at a certain temperature Tg,an. It was also found that the magnetization is irreversible below an irreversible temperature Ti(H) with respect to the heating-cooling procedures. The thermal characterization was carried out using differential scanning calorimetry DSC (DSC-Q100 by TA Instruments) and thermogravimetric analysis TGA (TGA-Q500 by TA Instruments). A (H,T) phase diagram that contains THo, TCurie,am, Ti(H), and Tg,an(H) for the sample of Fe70Nb10B20 under study is presented. The universality class of the above mater